Scanner module and image scanning apparatus employing the same

ABSTRACT

A scanner module and an image scanning apparatus employing the same. The scanner module comprises an illuminator for illuminating light on an object to be scanned. The illuminator includes a light emitting diode, a light guide extending in a main scanning direction to change a direction of the light received from the light emitting diode, and at least one elastic member to elastically support at least one longitudinal end of the light guide. As the light guide is elastically supported by the elastic member, convex deformation or bowing of an emission face of the light guide due to thermal expansion can be reduced.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/741,581 filed Jan. 15, 2013, which is pending, which is acontinuation of U.S. patent application Ser. No. 12/183,714, filed Jul.31, 2008, which issued Jan. 22, 2013 as U.S. Pat. No. 8,358,447, andclaims the benefit of Korean Patent Application No. 2007-0076640, filedon Jul. 31, 2007, and Korean Patent Application No. 10-2008-0065047filed on Jul. 4, 2008, which is a continuation of U.S. patentapplication Ser. No. 12/118,856 filed on May 12, 2008, which issued Jul.10, 2012 as U.S. Pat. No. 8,218,205 and which claims the disclosure ofthe benefit of Korean Patent Application No. 2007-0076640, each of whichis incorporated herein by reference in its entirety.This application isa reissue application of U.S. patent application Ser. No. 14/227,648,filed on Mar. 27, 2014, issued as U.S. Pat. No. 9,179,029 on Nov. 3,2015, which is a continuation of application Ser. No. 13/741,581, filedon Jan. 15, 2013, which issued as U.S. Pat. No. 9,204,006 on Dec. 1,2015, which is a continuation of application Ser. No. 12/183,714, filedon Jul. 31, 2008, which issued as U.S. Pat. No. 8,358,447 on Jan. 22,2013, which is a continuation of application Ser. No. 12/118,856, filedon May 12, 2008, which issued as U.S. Pat. No. 8,218,205 on Jul. 10,2012, and which claims the benefit of Korean Application No.10-2007-0076640, filed on Jul. 31, 2007 and Korean Application No.10-2008-0065047, filed on Jul. 4, 2008, in the Korean IntellectualProperty Office, the disclosures of which are incorporated herein byreference.

BACKGROUND

1. Field

The present invention relates to a scanner module and an image scanningapparatus employing the scanner module, and, more particularly, to amounting structure of a light guide in a scanner module.

2. Description of the Related Art

Generally, a scanner module may be employed in an image readingapparatus to read image from a desired portion of a document. To thisend, a scanner module may include an illuminator to irradiate light tothe portion of the document to be read and a focusing lens to focus thelight reflected from the portion of the document on an image sensor.

With recent development of inexpensive high-luminous-intensity whitelight-emitting diodes, a scanner module employing white light emittingdiodes as the light source has been developed.

An illuminator however also needs to have an appropriate lightdistribution to provide a uniform image output for each pixel. For thisreason, a light guide has been used to guide light, irradiated fromlight emitting diodes, to the desired illuminating position.

An example of an illuminator that employs light emitting diodes and alight guide, is disclosed in U.S. Pat. No. 6,357,903 B1 to Furusawa etal. (“Furusawa”), which was issued on Mar. 19, 2002).

In legacy illuminators, e.g., one described by Furusawa, a light sourceis provided at one end of an elongated transparent light guide that ismounted in a case by being slid lengthwise into the case. During thelengthwise insertion onto the case, damages to the light guide suffer,e.g., scratches, or the like, which may have adverse effect on thescanning performance. In addition, there is no structure to guide thelight guide into the proper mounting position, exacerbating thepossibility of damages, and resulting in imprecise assembly.

When light emitting diodes are used as the light source of anilluminator, the luminous intensity may be limited to a predeterminedlevel. While a higher current or voltage is supplied to the lightemitting diodes may result in the light emitting diodes producing lightwith enhanced luminous intensity, the increased power also raises thetemperature of the light emitting diodes, and, consequently, maydeteriorate the luminous intensity of light actually emitted by thelight emitting diodes.

Moreover, it is desirable that an illuminator be easy to assemble so asto allow mass production. A conventional light guide is formed as anelongated transparent member, which is prone to bending or bowing. It isthus also desirable to provide a guide holder that is capable ofsupporting the light guide while maintaining the light guide straight.

Furthermore, in the above-described conventional illuminator, both endsof the light guide are fixedly supported, causing the light guide tobend or bow along its length when the light guide lengthens due tothermal expansion by heat generated from the light source. Thesedeformation or damages, e.g., bending or scratches, or the like, of thelight guide causes variation in characteristics of light emittedtherethrough, and adversely affects the scanning performance and/orquality.

SUMMARY

Additional aspects and/or advantages of one or more embodiments will beset forth in part in the description which follows and, in part, will beapparent from the description, or may be learned by practice of one ormore embodiments of disclosure. One or more embodiments are inclusive ofsuch additional aspects.

Therefore, one or more embodiments relate to an illuminator for use inan image scanning apparatus to illuminate light on an object to bescanned.

In accordance with one or more embodiments, an illuminator for use in animage scanning apparatus to illuminate light on an object to be scannedmay include a light source configured to produce the light, a lightguide having an elongated shape with its length extending along a firstdirection, the light guide being configured to receive the light fromthe light source, and to change a direction of the received light, alight source holder to mount the light source to the light guide, and atleast one elastic member elastically supporting at least one oflongitudinal ends of the light guide.

A light guide according to one or more embodiments may include anincidence face formed on at least one longitudinal end of the lightguide, the light guide receiving the light from the light source throughthe incident face, and the elastic member elastically supports the lightsource, so as to cause the light source to be in close proximity to theincidence face of the light guide.

The elastic member may support the light source and may be disposed soas to elastically bias the light source toward the incidence face of thelight guide.

The elastic member may be made of a thermally conductive material.

The elastic member may include a metallic leaf spring.

The elastic member may be made of a resin material, and a radiatingmember made of a thermally conductive material may be provided betweenthe elastic member and the light source holder.

The illuminator may be integrally formed with a body of a scanningmodule, and the radiating member may extend outward from between theelastic member and the light source holder, and may be fixed to the bodyof the scanner module.

An illuminator according to one or more embodiments may include athermal coupling provided between a light source holder and a radiatingmember.

The light source holder may have a hole through which the light sourceis exposed.

An illuminator according to one or more embodiments may further includea guide holder having formed thereon a mounting recess into which thelight guide may be received, the guide holder may further include alight source mounting portion in which the light source holder ismounted, and the elastic member may be provided between a wall surfaceof the light source mounting portion and the light source.

The elastic member may include an elastic portion convexly raised toexhibit an elastic force, and supporting portions formed at both sidesof the elastic portion to allow the elastic member to be supported atboth ends of the light source mounting portion.

An illuminator according to one or more embodiments may further includea guide holder having formed thereon a mounting recess into which thelight guide may be received, the mounting recess possibly including anentrance portion, through which the light guide enters the mountingrecess, and at least one supporting protrusion formed at the entranceportion of the mounting recess to protrude into the mounting recess to,when the light guide is received in the mounting recess, be in aninterfering contact with the light guide to restrict movement of thelight guide in at least a second direction perpendicular to the firstdirection.

The light guide may be received into the mounting recess in a seconddirection substantially perpendicular to the first direction.

The elastic member may comprise a pair of elastic members, each of whichpair supporting a corresponding respective one of the longitudinal endsof the light guide.

In accordance with one or more embodiments, a scanning module for use inan image scanning apparatus for scanning an object may include anilluminator configured to illuminate a light on the object to bescanned; and a sensor configured to detect the light reflected from theobject. The illuminator may include a light source configured to producethe light, a light guide having an elongated shape with its lengthextending along a first direction, the light guide being configured toreceive the light from the light source, and to change a direction ofthe received light, a light source holder to mount the light source tothe light guide; and at least one elastic member elastically supportingat least one of longitudinal ends of the light guide.

The light source may face the incidence face of the light guide and theelastic member may support the substrate opposite a side of thesubstrate on which the light source is disposed so as to elasticallybias the light source toward the incidence face of the light guide.

The elastic member may be made of a thermally conductive material.

The elastic member may be made of a resin material, and a radiatingmember made of a thermally conductive material is provided between theelastic member and the light source holder.

The scanning module may further include a thermal coupling providedbetween the light source holder and the radiating member.

The scanning module may further include a guide holder having formedthereon a mounting recess into which the light guide may be received.The guide holder may further include a light source mounting portion inwhich the light source holder may be mounted, and the elastic member maybe provided between a wall surface of the light source mounting portionand the light source holder.

The elastic member may include a pair of elastic members, each of whichpair may support a corresponding respective one of the longitudinal endsof the light guide.

In accordance with one or more embodiments, an image scanning apparatusmay include a scanner module, a controller configured to control anoperation of the scanner module. The scanner module may include anilluminator configured to illuminate a light on an object to be scanned,and a sensor configured to detect the light reflected from the object.The illuminator may include a light source configured to produce thelight, a light guide having an elongated shape with its length extendingalong a first direction, the light guide being configured to receive thelight from the light source, and to change a direction of the receivedlight, a light source holder to mount the light source to the lightguide, and at least one elastic member elastically supporting at leastone of longitudinal ends of the light guide.

The light source may be facing the incidence face of the light guide andthe elastic member supporting the light source may be disposed so as toelastically bias the light source toward the incidence face of the lightguide.

The elastic member may be made of a thermally conductive material.

The elastic member may be made of a resin material, and a radiatingmember made of a thermally conductive material may be provided betweenthe elastic member and the light source holder.

In accordance with one or more embodiments, an image scanning apparatusmay further include a thermal coupling provided between the light sourceholder and the radiating member.

In accordance with one or more embodiments, an image scanning apparatusmay further include a guide holder having formed thereon a mountingrecess into which the light guide is received. The guide holder mayfurther include a light source mounting portion in which the lightsource holder may be mounted, and the elastic member may be providedbetween a wall surface of the light source mounting portion and thelight source holder.

The elastic member may include a pair of elastic members, each of whichpair may support a corresponding respective one of the longitudinal endsof the light guide.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

Various aspects and advantages of the embodiments of the invention willbecome apparent and be more readily appreciated from the followingdescription of the embodiments, taken in conjunction with theaccompanying drawings, of which:

FIG. 1 is a sectional view illustrating optical arrangement of a scannermodule in accordance with an embodiment of the present invention;

FIG. 2 is a perspective view of the scanner module in accordance with anembodiment of the present invention;

FIG. 3 is an exploded perspective view illustrating an illuminator inaccordance with a first embodiment of the present invention;

FIG. 4 is a perspective and partial sectional view of portions of theilluminator of FIG. 3;

FIG. 5 is a sectional view of the illuminator of FIG. 3;

FIG. 6 is a perspective view illustrating an embodiment of a lightsource holder of the illuminator of FIG. 3;

FIG. 7 is a sectional view of the portion “A” of FIG. 6;

FIG. 8 is a partial sectional view illustrating coupling of a guideholder and light source holder shown in FIGS. 2-7

FIG. 9 is a block diagram illustrating an image scanning apparatusemploying a scanner module in accordance with an embodiment of thepresent invention;

FIG. 10 is a perspective and a partial sectional view of an illuminatorin accordance with a second embodiment of the present invention;

FIG. 11 is an exploded and a partial sectional view of relevant portionsof an illuminator in accordance with a third embodiment of the presentinvention;

FIG. 12 is an exploded perspective view illustrating a scanner moduleincluding an illuminator in accordance with a fourth embodiment of thepresent invention;

FIG. 13 is a plan view illustrating coupling of a light source and lightsource holder provided in the scanner module shown in FIG. 12;

FIG. 14 is a view illustrating numerical analysis results of deformationof a light guide in response to thermal expansion of the light guidewhen no elastic member is provided;

FIG. 15 is a view illustrating numerical analysis results of deformationof a light guide in response to thermal expansion of the light guidewhen elastic members are provided;

FIG. 16 is a graph comparing temperatures of a light source in bothcases where the light source is elastically supported by metal elasticmembers and where no elastic member is provided;

FIG. 17 is a sectional view illustrating an embodiment of the mountingof the light guide mounted in an illuminator;

FIG. 18 is a view illustrating numerical analysis results of deformationof a light guide in response to thermal expansion of the light guidewhen no supporting protrusion is provided;

FIG. 19 is a view illustrating numerical analysis results of deformationof a light guide in response to thermal expansion of the light guidewhen supporting protrusions are provided; and

FIG. 20 is an exploded perspective view illustrating a scanner moduleincluding an illuminator in accordance with a fifth embodiment of thepresent invention.

DETAILED DESCRIPTION

Reference will now be made in detail to embodiments of the presentinvention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to like elementsthroughout. While the embodiments are described with detailedconstruction and elements to assist in a comprehensive understanding ofthe various applications and advantages of the embodiments, it should beapparent however that the embodiments can be carried out without thosespecifically detailed particulars. Also, well-known functions orconstructions will not be described in detail so as to avoid obscuringthe description with unnecessary detail.

FIG. 1 is a sectional view illustrating optical arrangement of a scannermodule 10 according to an embodiment of the present invention. Referringto FIG. 1, the scanner module 10 may be devised to scan an image acrossa sub scanning direction X. The scanner module 10 includes anilluminator 110, which irradiates a light to a document platform D, afocusing lens 120, which focuses the light reflected from a scan objectP, such as a document, or the like, disposed on the document platform D,and a sensor unit 130, which receives the light focused by the focusinglens 120 and senses an image based on the received light. The scannermodule 10 further includes a scanner module body 100 having an innerspace in which the focusing lens 120 and the sensor unit 130 may behoused. A seating recess 100a (See FIG. 2) may provided on the topportion of the scanner module body 100 for accommodating the illuminator110.

The illuminator 110 serves to irradiate light to the scan object P. Asshown in FIGS. 2 and 3, the illuminator 110 may include light source ofsources 111 that produce the light, and light source holders 112 towhich the light sources 111 are mounted. The illuminator 110 may furtherinclude light guides 113, the lengths of which extend along a mainscanning direction Y (orthogonal to the sub scanning direction X), andwhich are arranged to face and oppose the document platform D. Theilluminator 110 may further include a guide holder 114 having lightguide mounting portions 114a for mounting of the light guides 113 andlight source mounting portions 114b for mounting of the light sourceholders 112.

Referring again to FIG. 1, the focusing lens 120 is located between thedocument platform D and the sensor unit 130, and serves to focus thelight reflected from the scan object P onto the sensor unit 130.

The sensor unit 130 receives the light focused thereon by the focusinglens 120, and serves to detect an image of the scan object P based onthe received light. Depending on the particular scanning application,the sensor unit 130 may have a single-row configuration, or a multiplerow configuration, for scanning of Red/Green/Blue color images orRed/Green/Blue/Black-and-White images. Specifically, the sensor unit 130may include image sensors, e.g., charge coupled device (CCD) orcomplimentary metal oxide (CMOS) pixel elements, for respective colors,which are arranged in plural rows spaced apart from one another.

A plurality of reflecting mirrors 140 may further be provided betweenthe scan object P and the focusing lens 120. The reflecting mirrors 140serve to define a light path within the inner space of the scannermodule body 100. To this end, the reflecting mirrors 140 reflect thelight reflected from the scan object P, and change the light path todirect the light toward the focusing lens 120. Providing the pluralityof reflecting mirrors 140 may advantageously achieve the required lightfocusing distance between the scan object P and the sensor unit 130, andmay also result in a compact size of the scanner module body 100. In thepresent embodiment, the scanner module 10 is provided with fourreflecting mirrors 140, but the present invention is not so limited, andany number of reflecting mirrors can be selected for a particulardesign.

FIGS. 2 to 5 are a perspective view, an exploded perspective view, apartial perspective view, and a sectional view, respectively,illustrating the illuminator employed according to the first embodimentof the present invention. FIG. 6 is a perspective view illustrating thelight source holder according to an embodiment. FIG. 8 is a partialsectional view illustrating assembly of the guide holder and the lightsource holder shown in FIGS. 2-6.

Referring to the drawings, the illuminator 110 is employed in thescanner module 10, to irradiate light to the scan object P, which isdisposed on the document platform D, in the main scanning direction Ythat is substantially orthogonal to the sub scanning direction X of thescanner module 10.

The illuminator 110 includes light sources 111 producing light, thelight source holders 112 to which the light sources 111 are mounted, thelight guides 113 longitudinally arranged along the main scanningdirection Y to face the document platform D, and the guide holder 114,in which the light guides 113 are mounted.

Each of the light sources 111 may include a substrate 111a mounted tothe light source holder 112, and light emitting diodes 111b formed onthe substrate 111a to irradiate light upon receiving power through thesubstrate 111a. In an embodiment, the light emitting diodes 111b may bewhite light emitting diodes.

The light guides 113 change a direction of the light irradiated from thelight sources 111, so as to direct the light to an image reading regionon the document platform D. In one embodiment, to enhance the luminousintensity of light to be directed to the image reading region, theplurality of light guides 113 may be provided.

The light guides 113 are made of a transparent material such as glass,plastic, or the like, and have an elongated shape, the length of whichextending along the main scanning direction Y. Each of the light guides113 includes at least one incidence face 113a, guide faces 113b and anemission face 113c.

The incidence face 113a receives the light from the corresponding lightemitting diode 111b. The incidence face 113a is formed on at least oneof both longitudinal ends of the respective light guides 113. Here, thelight source 111 is mounted to the light source holder 112 such that thelight source 111 faces the incidence face 113a of the light guide 113.

The emission face 113c opposes the document platform D, through whichthe light diffused and reflected by the guide faces 113b is emitted. Inone embodiment, the emission face 113c may form a collimating lens.

The guide faces 113b are formed at both longitudinal sides of the lightguide 113. If light is introduced through the incidence face 113a viatotal internal reflection, the guide faces 113b guide the direction ofthe light, allowing the light to be emitted throughout the emission face113c.

The reflecting face 113d reflects the light, introduced thereto throughthe incidence face 113a, toward the emission face 113c. The reflectingface 113d is formed at the light guide 113 at an opposite side of theemission face 113c. For reflection of light, the reflecting face 113dhas a light reflecting pattern defined by convex and concave portions.

In the present embodiment, a pair of the light guides 113 is arranged tobe adjacent to each other along the sub scanning direction X. The pairof light guides 113 may be tilted towards each other to direct the lightto the image reading region without interfering with the light reflectedfrom the scan object P. That is, as shown in FIG. 1, center axes C1 andC2 of light having passed through the two respective light guides 113are tilted with respect to the center optical axis Z.

In the embodiment shown, a pair of the light sources 111 is provided foreach of the light guides 113, a pair of the light emitting diodes 111bbeing installed on the substrate 111a of each light source 111. Withthis configuration, the two light emitting diodes 111b of each of thepair of light sources 111 can irradiate the light on each incidence face113a formed at both ends of each of the pair of light guides 113.

In addition, a light source holders 112 is provided on each longitudinalends of the guide holder 114 such that a light source 111 is provided oneach of the ends of each light guide 113. When light is irradiated fromthe light source 111 provided at one end of a light guide 113, and isintroduced to the light guides 113 through the incidence faces 113afacing the light source 111, in order to prevent the light from leakingfrom the light guides 113 through the incidence faces 113a at the otherend, the pair of light source holders 112 are arranged to cover bothincidence faces 113a of the respective light guides 113, the lightsource holders 112 being adapted to reflect the light. That is, the pairof light source holders 112 covers the pair of incidence faces 113a ofeach light guide 113, thereby preventing the light, introduced into thelight guide 113 through the incidence faces 113a of on one end, fromleaking from the light guide 113 through the incidence face 113a on theother end of the light guide 113.

In an embodiment, preferably, the light source holders 112 are made of awhite material to reflect and diffuse light, the material having a lightreflectivity of 70% or greater. With adoption of the light sourceholders 112 to prevent the light, irradiated from the light sources 111into the light guides 113, from leaking from the light guides 113through the incidence faces 113a, the illuminator 110 can achievegreater luminous intensity of light using the same light sources 111.

While the above embodiment is described to include a pair of lightsources 111 at each end of the light guides 113 via the pair of lightsource holders 112, but this configuration is given only as an example.Alternatively, a single light source 111 may be mounted to only one endof each of the light guides 113 via a single light source holder 112.

According to an embodiment, the guide holder 114 may serve to guidemounting positions of the light guides 113 and the light sources 111. Tothis end, the guide holder 114 is formed with at least one light sourcemounting portion 114b to which the light source holder 112 may bemounted to provide a light source 111 on at least one end of each of thelight guides 113, and the light guide mounting portions 114a in whichthe light guides 113 are to be mounted.

Each light guide mounting portion 114a may be recessed into the guideholder 114 extending longitudinally along the main scanning direction Y,and has a shape corresponding to that of the light guide 113. Forexample, in the embodiment shown, the light guide mounting portion 114amay have a trapezoidal cross-sectional shape having an inwardly taperedcross section. In the embodiment, the pair of the light guide mountingportions 114a are arranged adjacent each other along the sub scanningdirection X, and extend parallel to each other along the main scanningdirection Y such that the pair of light guides 113 can be mountedparallel to each other.

Preferably, the light guide 113 is inserted into the light guidemounting portion 114a by being moved in a direction orthogonal to thelongitudinal direction of the light guide 113. If the light guide 113 isinserted into the longitudinal direction of the light guide mountingportion 114a, scratches may occur on an outer surface of the light guide113. Inserting the light guide 113 in a direction orthogonal to thelongitudinal direction thereof may reduce the possibility of scratchingthe light guides 113. For example, in the embodiment shown, the lightguide mounting portion 114a has, e.g., a trapezoidal cross section withits height significantly smaller than its length. Therefore, when alight guide 113 is inserted into the light guide mounting portion 114aalong the height of the light guide mounting portion 114a, i.e.orthogonal to the longitudinal direction of the light guide 113, thecontact distance between the light guide 113 and the light guidemounting portion 114a may be substantially shorter that when the lightguide 113 is received into the recess in lengthwise direction, andconsequently, damage to the light guide 113 can be minimized.

The guide holder 114 may be made of a flexible material, which iselastically deformable in response to a pressing force. For example,before the light guide 113 is inserted into the light guide mountingportion 114a, the light guide mounting portion 114a, as represented bythe dotted line in FIG. 5, may have a narrower initial inner space thanthe space required for mounting of the light guide 113.

When the light guide 113 is received into the light guide mountingportion 114a, as shown in FIG. 5, the light guide mounting portion 114aexpands by the insertion of the light guide 113, preventing unwantedmovement of the light guide 113 after installation.

According to an embodiment, the illuminator 110 may further includespacers 114c provided on the inner surface of the light guide mountingportion 114a to support the light guide 113.

Once the light guide 1133 is inserted into the light guide mountingportion 114a that includes the spacers 114c, the light guide 113 can besupported by the spacers 114c while allowing gaps between the lightguide 113 and the inner surface of the light guide mounting portion114a. Providing the spacers 114c may further alleviate the problem ofincompletely supporting the light guide 113 due to spatial deformationof the light guide mounting portion 114a resulting during manufacture ofthe guide holder 114. This consequently reduce bending of the lightguide 113, and helps to maintain straightness of the light guide 113.

A plurality of spacers 114c may be spaced apart from one another alongthe longitudinal direction of the light guide 113. For example, in thepresent embodiment, the spacers 114c may be provided at the center andat opposite ends of the light guide mounting portion 114a along itslength. As shown in FIG. 5, the spacers 114c may be arranged on the sidewall surfaces and bottom surface of the light guide mounting portion114a, so as to support the light guide 113 in three directions.

When a pair of the spacers 114c are arranged on the side wall surfacesof the light guide mounting portion 114a, the distance between thespacers 114c on opposite wall surfaces may be made smaller than thewidth of the light guide 113 to be located between the spacers 114c.With this configuration, as the light guide 113 is inserted into thelight guide mounting portion 114a, the guide holder 114 is elasticallydeformed to provide a required installation space for the light guide113, and the light guide 113 can come into pressing contact with therespective spacers 114c. In one embodiment, the spacers 114c may beformed integrally with the guide holder 114, which may improve assemblyefficiency, and may reduce manufacturing costs.

The light source holder 112 may include a fixing portion 112a to keepthe light guide 113 in place. The fixing portion 112a protrudes to havean inner contour corresponding to the contour of the emission face 113cof the light guide 113, and can be made to come into direct or indirectcontact with the emission face 113c of the light guide 113 so as toprevent vertical movement of the light guide 113.

For example, as shown in FIG. 6, the light source holder 112 may furtherinclude a fixing rib 112b formed on the inner edge surface of the fixingportion 112a. Once the light guide 113 is mounted in the light guidemounting portion 114a, the fixing rib 112b may come into partial contactwith the light guide 113, and can keep the light guide 113 in position.

During the coupling of the light source holder 112 to the guide holder114, the fixing rib 112b and the light guide 113 move relatively eachother while being in contact, possibly causing the light guide 113 to bescratched. Thus, in one embodiment, the fixing rib 112b may be taperedas shown in FIG. 7. The tapered fixing rib 112b may reduce possibledamages to the light guide 113 during the installation of the lightsource holder 112 in the guide holder 114.

To address the possible thermal expansion of the light guide 113,according to an embodiment shown in FIG. 7, the fixing rib 112b may beprovided with a neck portion 112c, which forms a recessed portionbetween the fixing portion 112a and the fixing rib 112b.

If a greater pressure is applied to an outer surface of the fixing rib112b as the light guide 113 is thermally deformed, the neck portion 112callows elastic movement of the fixing rib 112b. As a result, the lightguide 113 can be stably supported at a fixed position without damagingthe fixing rib 112b. The structure of the neck portion 112c is describedonly by way of an example for addressing thermal deformation of thelight guide 113, and does not limited the present embodiments to theparticular structure. Various other shapes or structures can also beemployed to account for the thermal expansion of the light guide 113.For example, when the light source holder 112, the fixing portion 112aand/or the fixing rib 112b itself is made of an elastically deformableflexible material, the light source holder 112 can also stably supportthe light guide 113.

In addition, the illuminator 110 may further include positioning guides112d and 114d to set the mounting position of the light source holder112 relative to the guide holder 114. The positioning guides, 112d and114d are shaped to match each other, and are arranged to be opposingpositions on the guide holder 114 and the light source holder 112,respectively. When coupling the light source holder 112 to the guideholder 114, the coupling position can be set on the basis of thepositioning guides 112d and 114d, making rapid and accurate couplingbetween the guide holder 114 and the light source holder 112 possible.

Preferably, the light source holder 112 may be capable of beingsnap-fitted to the mounting portion 114b of the guide holder 114.Snap-fitting may not require any screws or bonding adhesives and,therefore, advantageously enables easy coupling.

The light source holder 112, as shown in FIG. 3, can be coupled to themounting portion 114b in a direction substantially parallel thelongitudinal direction of the light guide 113. To that end, to mount thelight source holder 112 in the mounting portion 114b, hook members 112eand holding protrusions 114e may be provided.

The hook members 112e, as shown in FIGS. 6 and 8, may extend from asurface of the light source holder 112 facing the guide holder 114, andthe holding protrusions 114e may be provided at positions of the guideholder 114 corresponding to the mounted positions of the respective hookmembers 112e. When the hook members 112e engage the holding protrusions114e, the light source holder 112 may be coupled to the guide holder114.

While in the above embodiment, the light guide holder 112 is describedto have formed therewith the hook members 112e, and the guide holder 114as including the holding protrusions 114e, but the present invention isnot so limited. For example, the respective locations of the hookmembers and holding protrusions may be reversed.

In addition, the hook members 112e are not limited to theabove-described configuration. For example, according to a secondembodiment of illuminator shown in FIG. 10, each hook member 212e of thelight source holder 212 may be formed, at the distal tip end thereof,with a relatively large width portion while the light source mountingportion 214b of a guide holder 214 may be provided with a recess havinga shape corresponding to that of the hook member 212e. Accordingly, thelight source holder 212 can be coupled to the guide holder 214 as thehook member 212e is snap-fitted in the mounting portion 214b as shown inFIG. 10.

Referring to FIG. 11 illustrating an illuminator according to a thirdembodiment, a light source holder 312 may be fitted into a mountingportion 314b of a guide holder 314 in a direction orthogonal to thelongitudinal direction of a light guide 313. For example, an illuminatorof this embodiment may further include hook members 312e and holdingprotrusions 314e, to stably fit the light source holder 312 into themounting portion 314b.

The hook members 312e, as shown in FIG. 11, may protrude downward fromside edges of the light source holder 312, and the holding protrusions314e may be provided at positions of the guide holder 314 correspondingto the mounted position of the respective hook members 312e.Accordingly, as the hook members 312e engage the holding protrusions314e, the light source holder 312 can be coupled to the guide holder314.

When the light source holder 312 is coupled to the guide holder 314 inthe above-described direction, as there is substantially no risk of thecontact position between the fixing rib of the light source holder 312and the light guide 313 being changed during assembly, the generation ofscratches can thus be substantially avoided.

The above-described configuration of the illuminator, along with one ormore features of previously described embodiments, advantageous allowsprecise positioning an/or quick coupling of the light guide 313 and thelight source 311. In addition, the light guide 313 can be firmlysupported to maintain straightness thereof.

Although the illuminator 110 in accordance with the first embodiment ofthe present invention includes the guide holder 114 to be mounted intothe scanner module body 100 after the light guides 113, light sources111 and light holders 112 are mounted to the guide holder 114, thepresent invention is not so limited. For example, referring to FIG. 12illustrating an illuminator according to a fourth embodiment, instead ofusing the guide holder 114, an illuminator 410 of a scanner module 40includes light guides 413, light sources 411 and light source holders412, and a scanner module body 400, on which the light guide mountingportions 400a for mounting of the light guides 413 and the light sourcemounting portions 400b for mounting of both the light sources 411 andthe light source holders 412 are provided. With this configuration, thelight guides 413, light sources 411 and light source holders 412 can bedirectly mounted into the scanner module body 400.

The light guide mounting portions 400a extend along the main scanningdirection Y, i.e. in the longitudinal direction of the light guides 413.The light source mounting portions 400b are formed, at both ends of thelight guide mounting portions 400a, to have a larger width than thewidth of the light guide mounting portions 400a. In the presentembodiment, a pair of the light guides 413 are mounted in the scannermodule body 400 such that they are parallel to each other in the subscanning direction X, and for mounting of the pair of light guides 413,a pair of the light guide mounting portions 400a are provided parallelto each other in the sub scanning direction X.

In this embodiment, a light guide 413 is mounted in the light guidemounting portion 400a in such a manner that at least one of thelongitudinal ends thereof is elastically supported by an elastic member414. This serves to minimize deformation of the light guide 413 causedwhen the light guide 413 increases in length due to thermal expansion byheat generated from the light sources 411. If the light guide 413increases in length due to thermal expansion, the light guide 413 maybecome convexly deformed, or bowed, at the center of an emission face413c, causing variation in characteristics of light emitted through thelight guide 413 and deterioration in image scanning performance.

By elastically supporting at least one of end of the light guide 413using the elastic member 414, even if the light guide 413 increases inlength due to thermal expansion, the elastic member 414 can partiallycompensate for the increase in the length of the light guide 413 viaelastic deformation thereof as shown in FIG. 13. This substantiallyreduces the emission face 413c of the light guide 413 from being bent orbowed.

FIG. 14 is a view illustrating results of numerical analysis ofdeformation of the light guide 413 when both the ends of the light guide413 are fixedly supported, and FIG. 15 is a view illustrating results ofnumerical analysis of deformation of the light guide 413 when both endsof the light guide 413 are elastically supported by the elastic members414.

As can be seen from FIGS. 14 and 15, the light guide 413 has adeformation amount of about 0.021 mm when both the ends of the lightguide 413 are fixedly supported, whereas the light guide 413 has adeformation amount of 0.012 mm when both the ends of the light guide 413are elastically supported by the elastic members 414. Accordingly, inthis example, it can be appreciated that supporting both the ends of thelight guide 413 via the elastic members 414 may reduce the deformationamount of the light guide 413 to about half.

When the length of the light guide 413 varies according to heatgenerated from the light sources 411, an incidence face 413a of thelight guide 413 may become spaced further apart from a correspondinglight emitting diode 411b of the light source 411. In this case, lightloss may occur as the light irradiated from the light emitting diode411b passes through air between the light emitting diode 411b and theincidence face 413a. Therefore, to minimize the light loss, it ispreferred that the incidence face 413a provided at either end of thelight guide 413 come into close contact with the corresponding lightemitting diode 411b of the light source 411.

In an embodiment, to maintain the proper distance between the incidencesurface 413a and the light emitting diode 411b, the light source 411 ismounted to either end of the light guide 413 via the light source holder412, and the elastic member 414 is provided between the light source 411and a wall surface of the light source mounting portion 400b toelastically support the light guide 413 indirectly by way of the lightsource 411. When supporting the light guide 413 in this manner using theelastic member 414 with the light source 411 being interposed betweenthe incidence surface 413a and the elastic member 414, the elasticmember 414 can reduce the possible bowing of the light guide 413, andmay also allow the light emitting diode 411b of the light source 411 tomaintain a sufficiently close proximity to the corresponding incidenceface 413a of the light guide 413, resulting in reduction of light loss.

In the present embodiment, although the light emitting diodes 411b aremounted to the light source holder 412 in a state of being mounted on asubstrate 411a, the present invention is not limited thereto. Forexample, after the light emitting diodes 411b are directly mounted tothe light source holder 412 without a structure corresponding to thesubstrate 411a, the light source holder 412 is elastically supported bythe elastic member 414, whereby the light emitting diodes 411b can comeinto close contact with the incidence face 413a of the light guide 413.

Referring again to FIG. 12, the elastic member 414 according to anembodiment may be a leaf spring. The elastic member 414 in the form of aleaf spring consists of a center elastic portion 414a, which is convexlyraised to exhibit an elastic force so as to elastically support thelight source holder 112, and supporting portions 414b which are definedat both sides of the elastic portion 414a to allow the elastic member414 to be supported in the light source mounting portion 400b. Theelastic member 414 may be made of a material exhibiting high thermalconductivity, such as metallic material, to thus serve, in addition toproviding the elastic support, as a radiating member to radiate heatgenerated from the light source 411 away from the light source 411.

FIG. 16 is a graph showing the measured temperatures of the light source411 in both cases of when the metal elastic members 414 is used and whenit was not. In the graph of FIG. 16, the dotted curve represents thetemperature variation when the elastic member 414 was not used, and thesolid curve represents the temperature variation when the metal elasticmember 414 is used. As can be seen from the graph, in this example, theuse of the metal elastic member 414 can lower the temperature of thelight source 411 by approximately 17.degree. C.

According to an embodiment, to more effectively restrict the emissionface 413c of the light guide 413 from being deformed by heat generatedfrom the light sources 411, supporting protrusions 415 protrude from anentrance of the light guide mounting portion 400a, so as to support apart of the emission face 413c of the light guide 413.

Specifically, the supporting protrusions 415 are integrally formed withthe scanner module body 400. The plurality of supporting protrusions 415protrude in the sub scanning direction X and are spaced apart from oneanother in the main scanning direction Y. As shown in FIG. 17, when apart of the emission face 413c of the light guide 413 is supported bythe supporting protrusions 415, the supporting protrusions 415 canrestrict deformation of the light guide 413 even if the light guide 413thermally expands due to heat generated from the light sources 411. Inthe present embodiment, the pair of light guide mounting portions 400aare arranged parallel to each other in the sub scanning direction X, andeach supporting protrusion 415 protrudes in the sub scanning direction Xfrom one side of the light guide mounting portion 400a so as to supporta part of the emission face 413c of the light guide 413.

FIG. 18 is a view illustrating numerical analysis results of deformationof the light guide 413 when not using the supporting protrusion 415, andFIG. 19 is a view illustrating numerical analysis results of deformationof the light guide 413 when using three supporting protrusions 415.

As can be seen from FIGS. 18 and 19, in this example, the light guide413 has a deformation amount of about 0.021 mm when the supportingprotrusion 415 was not used, whereas the light guide 413 has adeformation amount of about 0.014 mm when the emission face 413c of thelight guide 413 is supported by the supporting protrusions 415.Accordingly, it can be appreciated that use of the supportingprotrusions 415 can substantially reduce the deformation amount of thelight guide 413.

As described above, when the light guide 413 is elastically supported bythe elastic members 414 and/or when the emission face 413c of the lightguide 413 is supported by the supporting protrusions 415, deformation ofthe light guide 413 can be reduced. Accordingly, to minimize deformationof the light guide 413, as described with relation to the presentembodiment, it is preferred that both the ends of the light guide 413 beelastically supported by the elastic members 414 and that the emissionface 413c of the light guide 413 be supported by the plurality ofsupporting protrusions 415.

The supporting protrusions 415 provided at the entrance of the lightguide mounting portion 400a as described above, further, have the effectof preventing the light guide 413 from being separated from the lightguide mounting portion 400a even when subjected to vibration or shockduring, e.g., transportation of the scanner module 40 or of a variety ofappliances in which the scanner module 40 is included.

As a result of performing a drop test from a height of 30 cm, simulatinga drop that may be experienced by the scanner module 40 duringtransport, under several conditions of different numbers of supportingprotrusions 415, the light guide 413 was separated from the light guidemounting portion 400a when two supporting protrusions 415 were provided,but remained in the light guide mounting portion 400a when threesupporting protrusions 415 were provided. Accordingly, it is preferablethat three or more supporting protrusions 415 be formed to protectagainst external vibration or shock, in order to prevent the light guide413 from being separated from the light guide mounting portion 400a ofthe scanner module body 400.

Referring again to FIG. 12, a reflecting face 413d provided at the lightguide 413 has a convex and concave pattern. With this configuration, apart of the light, irradiated from the light emitting diodes 411b andintroduced into the light guide 413, may leak from the reflecting face413d of the light guide 413 to the outside, causing light loss.Therefore, a reflecting plate 418 is disposed at the rear side of thereflecting face 413d of the light guide 413, to reflect the light,leaked from the reflecting face 413d to the outside of the light guide413, toward the reflecting face 413d, so as to allow the reflected lightto be again introduced into the light guide 413 through the reflectingface 413d. In the present embodiment, a pair of light guides 413 areprovided and therefore, a pair of reflecting plates 418 are providedsuch that the reflecting plates 418 are provided at the rear side of thereflecting faces 413d of the pair of light guides 413, respectively. Asupporting piece 418a is formed at one side of each reflecting plate418, to be supported on one side of the light guide 413. Through thesupporting piece 418a, the reflecting plate 418 can be stably mounted inthe corresponding light guide mounting portion 400a.

While an embodiment is described above to include an elastic member 414,in the form of a metal leaf spring, to elastically supports the lightguide 413 and the light source 411, the present invention is not solimited. For example, an elastic member 514, made of an elastic resinmaterial such as rubber, may alternatively be used as shown in FIG. 20.

Referring to FIG. 20, the elastic resin member 514 may exhibit poorthermal conductivity, and may not be as effective in removing the heatgenerated by the light source 511. In an embodiment, a radiating member516, made of material that has a sufficiently high thermal conductivity,may be provided between the elastic member 514 and the light source 511.

One end of the radiating member 516 may be located between the elasticmember 514 and the light source 511 while the other end of the radiatingmember 516 extends out of a light source mounting portion 500b, and ismounted to a portion of the scanner module body 500. The heat generatedfrom the light source 511 is transferred along the radiating member 516,and is radiated via heat exchange with air outside the light sourcemounting portion 500b. As a result, heat generated from the light source511 can be radiated.

In the above-described configuration, thermal conductivity between thelight source 511 and the radiating member 516 is proportional to thecontact area between the light source 511 and the radiating member 516.When facing surfaces of the light source 511 and the radiating member516 are not flat and thus, have a relatively small contact area betweenthem, a thermal coupling 517 may be provided between the light source511 and the radiating member 516 to enhance the transfer of heatgenerated from the light source 511 to the radiating member 516. Thethermal coupling 517 may be made of a material exhibiting high thermalconductivity, and may be configured to closely contact both facingsurfaces of the light source 511 and the radiating member 516. Thethermal coupling 517 can indirectly maximize the contact area betweenthe light source 511 and the radiating member 516, and, consequently,can allow heat generated from the light source 511 to be effectivelytransmitted to and radiated by the radiating member 516.

In the present embodiment, although the thermal coupling 517 is providedbetween the light source 511 and the radiating member 516, when thelight emitting diodes 511b are directly mounted to the light sourceholder 512 without a structure corresponding to the substrate 511a, thethermal coupling 517 may be provided between the light source holder 512and the radiating member 516.

FIG. 9 is a block diagram illustrating an image scanning apparatusemploying a scanning module, various embodiments of which have beendescribed above. Referring to the drawing, the image scanning apparatusmay include the scanner module 10, and an image processor 20 to processan image obtained from the scanner module 10. Here, the image scanningapparatus in accordance with the present invention may include, e.g., aMulti-Functional Printer (MFP), a digital copier, a scanner, afacsimile, or the like.

The scanner module 10 is substantially identical to the embodimentsvariously described above, a detailed description of which need not berepeated. The image processor 20 may include at least one of a fileproducer 21 to produce an image file from an image obtained from thesensor unit 130 (FIG. 1) and an image former 22 to form an image on aprinting medium on the basis of the obtained image.

The file producer 21 may be, e.g., a controller that may also controloperations of various components of the image scanning apparatus,including, e.g., the scanner module. To this end, according to anembodiment, the controller may be, e.g., a microprocessor, amicrocontroller or the like, that includes a CPU to execute one or morecomputer instructions to implement the various control operations of thescanning apparatus, and may further include a memory device, e.g., aRandom Access Memory (RAM), Read-Only-Memory (ROM), a flesh memory, orthe like, to store the one or more computer instructions. The method inwhich the controller controls various components of an image scanningapparatus is similar to that of well-known image scanning apparatuses,detailed description thereof is thus unnecessary.

The image former 22 may include one or more of components of an imageforming apparatus, for example, of an electro-photographic printingapparatus, that includes, e.g., a printing medium feeding unit thatholds, picks up and feeds printing medium, an exposure unit for drawinga latent image using light on a photosensitive surface, a developingunit to develop the latent image with toner, a transfer unit to transferthe toner image onto the printing medium, a fixing unit to fuse thetoner image sufficiently permanently on the printing medium and adischarging unit for discharging a printing medium on which an image hasbeen fixed. As known to those skilled in the art, there are manyavailable and known other various image forming mechanisms.

While the above embodiments are generally described in references toexamples of a charge coupled device module (CCDM) type scanner module,in which a light source and a plurality of reflecting mirrors constitutea single module, the present invention is also applicable to other typesof scanning module, including, e.g., a Mirror Moving Type (MMT), inwhich a light source and a single reflecting mirror constitute onemodule and two reflecting mirrors constitute another module.

Although embodiments of the present invention have been shown anddescribed, it would be appreciated by those skilled in the art thatchanges may be made in this embodiment without departing from theprinciples and spirit of the invention, the scope of which is defined inthe claims and their equivalents.

What is claimed is:
 1. A scanner module for use in an image scanningapparatus to scan an object, comprising: a light source configured toproduce light emitted by the scanner module to scan the object; and aheat radiating member made of an elastically deformable material tocause the light source to come into close contact with the heatradiating member and configured to dissipate heat generated from thelight source when the light source produces the light.
 2. The scannermodule according to claim 1, wherein the radiating member comprises ametallic leaf spring.
 3. The scanner module according to claim 1,wherein the heat radiating member is made of a thermally conductivematerial.
 4. The scanner module according to claim 1, wherein the lightsource comprises a light emitting diode.
 5. An image scanning apparatus,comprising: a scanner module, wherein the scanner module comprises: anilluminator configured to illuminate light on an object to be scanned;and a sensor configured to detect the light reflected from the object,wherein the illuminator comprises: a light source configured to producethe light illuminated on the object to scan the object; and a heatradiating member to dissipate heat generated from the light source whenthe light source produces the light, the heat radiating member beingmade of an elastically deformable material.
 6. The image scanningapparatus according to claim 5, wherein the heat radiating member ismade of a thermally conductive material.
 7. The image scanning apparatusaccording to claim 5, wherein the light source comprises a lightemitting diode.
 8. A scanner module for use in an image scanningapparatus to scan an object, comprising: a light source configured toproduce light; a heat radiating member configured to dissipate heatgenerated from the light source; and a light guide having an elongatedshape with its length extending along a first direction, the light guidebeing configured to receive the light from the light source, and tochange a direction of the received light, wherein the heat radiatingmember is in contact with the light source.
 9. The scanner moduleaccording to claim 8, wherein the light source is mounted on thelongitudinal end of the light guide.
 10. The scanner module according toclaim 9, wherein the light source comprises a pair of light sources, andwherein the heat radiating member comprises a pair of heat radiatingmembers to come contact with the pair of light sources respectively. 11.The scanner module according to claim 8, wherein the heat radiatingmember includes a first portion in contact with the light source todissipate heat generated from the light source and a second portionextending from the first portion without making contact with the lightsource.
 12. An image scanning apparatus, comprising: a scanner module,wherein the scanner module comprises: an illuminator configured toilluminate light on an object to be scanned; and a sensor configured todetect the light reflected from the object, wherein the illuminatorcomprises: a light source configured to produce the light; a light guidehaving an elongated shape with its length extending along a firstdirection, the light guide being configured to receive the light fromthe light source, and to change a direction of the received light; and aheat radiating member to dissipate heat generated from the light source,and wherein the heat radiating member is in contact with the lightsource.
 13. The image scanning apparatus according to claim 12, whereinthe heat radiating member is a made of an elastically deformablematerial to cause the light source to come into close contact with theheat radiating member.
 14. The image scanning apparatus according toclaim 13, wherein the radiating member comprises a metallic leaf spring.15. The image scanning apparatus according to claim 12, wherein thelight source holder is mounted on the longitudinal end of the lightguide.
 16. The image scanning apparatus according to claim 15, whereinthe light source comprises a pair of light sources, and wherein the heatradiating member comprises a pair of heat radiating members to come incontact with the pair of light sources respectively.
 17. The imagescanning apparatus according to claim 12, wherein the heat radiatingmember includes a first portion in contact with the light source todissipate heat generated from the light source and a second portionextending from the first portion without making contact with the lightsource.
 18. An image forming apparatus comprising: a document bed; and ascanning module operable to scan a document placed on the document bed,the scanning module including an illuminator to illuminate light ontothe document to be scanned, and a sensor to detect the light reflectedby the document, the illuminator including: a first light source; firstlight guide to receive light produced from the first light source; asecond light source; a second light guide to receive light from thesecond light source, each of the first light guide and the second lightguide having an elongated shape with an incidence face formed on one oflongitudinal ends thereof to receive light, each of the first lightguide and the second light guide to change a direction of the lightreceived through the incidence face; a heat radiating member made of anelastically deformable material to cause the first light source to comeinto close contact with the heat radiating member and to dissipate heatgenerated from the first light source when the first light sourceproduces the light; and a first light source holder having a reflectivematerial at least on a side surface thereof facing the incidence face ofthe first light guide, the first light source being mounted to the firstlight source holder, wherein the first light guide and the second lightguide includes: a first guide face, a second guide face, an emissionface provided between the first guide face and the second guide face toemit light from the respective light guide to the document to bescanned, and a reflecting face located opposite to the emission face toreflect light received through the incidence face, wherein each of thefirst guide face and the second guide face extends between thelongitudinal ends of the first light guide and the second light guide,respectively, such that a first plane corresponding to the first guideface forms an acute angle with a second plane corresponding to thesecond guide face.
 19. The image forming apparatus of claim 18, whereinthe reflective material of the first light source holder has a lightreflectivity of 70% or greater.
 20. The image forming apparatus of claim18, wherein the reflective material of the first light source holder ismade out of a white material.
 21. The image forming apparatus of claim18, wherein the first light source and the second light source include alight emitting diode, respectively.
 22. The image forming apparatus ofclaim 18, further comprising a second light source holder having areflective material at least on a side surface thereof facing theincidence face of the second light guide, the second light source beingmounted to the second light source holder.
 23. The image formingapparatus of claim 22, wherein the reflective material of the secondlight source holder has a light reflectivity of 70% or greater.
 24. Theimage forming apparatus of claim 22, wherein the reflective material ofthe second light source holder is made out of a white material.
 25. Ascanner module for an image forming apparatus to scan an object,comprising: a first light source; a first light guide to receive lightproduced from the first light source; a second light source; a secondlight guide to receive light produced from the second light source, eachof the first light guide and the second light guide having an elongatedshape with an incidence face formed on one of longitudinal ends thereofto receive light, each of the first light guide and the second lightguide to change a direction of the light received through the incidenceface; and a heat radiating member made of an elastically deformablematerial to cause the first light source to come into close contact withthe heat radiating member and to dissipate heat generated from the firstlight source when the first light source produces the light; and a firstlight source holder having a reflective material at least on a sidesurface thereof facing the incidence face of the first light guide, thefirst light source being mounted to the first light source holder,wherein the first light guide and the second light guide includes: afirst guide face, a second guide face, an emission face provided betweenthe first guide face and the second guide face to emit light from therespective light guide to the object to be scanned, and a reflectingface located opposite to the emission face to reflect light receivedthrough the incidence face, wherein each of the first guide face and thesecond guide face extends between the longitudinal ends of the firstlight guide and the second light guide, respectively, such that a firstplane corresponding to the first guide face forms an acute angle with asecond plane corresponding to the second guide face.
 26. The scannermodule of claim 25, wherein the reflective material of the first lightsource holder has a light reflectivity of 70% or greater.
 27. Thescanner module of claim 25, wherein the reflective material of the firstlight source holder is made out of a white material.
 28. The scannermodule of claim 25, wherein the first light source and the second lightsource include a light emitting diode, respectively.
 29. The scannermodule of claim 25, further comprising a second light source holderhaving a reflective material at least on a side surface thereof facingthe incidence face of the second light guide, the second light sourcebeing mounted to the second light source holder.
 30. The scanner moduleof claim 29, wherein the reflective material of the second light sourceholder has a light reflectivity of 70% or greater.
 31. The scannermodule of claim 29, wherein the reflective material of the second lightsource holder is made out of a white material.